Process of coating and dyeing textile



United States Patent p 7 2,733,975 PROCESS OF COATING AND DYEING TEXTILEFIBERS AND RESULTANT ARTICLE Thomas C. Whither, Elizabeth, N. J.

No Drawing. Application July 19, 1950,

Serial No. 174,777 7 17 Claims. (Cl. 818) This invention relates to thetreatment of textile fibers impregnated with an alkali-copper complex,sericeous material and (in some instances) an alkaline agent. Itinvolves particularly the treatment of such impregnated fibers wherebyremoval of the alkali-copper complex and of the alkaline agent (ifpresent) is effected and textile,

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centration of acidic agent should be the same or substan- No. 2,565,832,is disclosed a procedure whereby an disclosed a process whereby anaqueous solution of an alkylolamine-copper complex and sericeousmaterial can be prepared (for impregnation of textile fibers) in whichthe proportion of alkaline agent (e. g., sodium or potassium hydroxide)is very-small. In my copending application, Ser. No. 162,385, now U. S.Pat. No. 2,675,326, is disclosed employment of aqueous solutions inwhich an alkali metal hydroxide or a tetra-alkyl ammonium hydroxideserves as both the copper complex-forming agent and as the alkalineagent.

In all of the above disclosed methods, the fibers after impregnationwith the aqueous solution of copper complex and sericeous material (andwhile they are still wet or damp and in some instances after theimpregnated fibers have been dried) are washed with an aqueous solutionof an acidic agent which forms water-soluble salts with thealkali-copper complex and with the alkaline agent (if present).Afterwards, the fibers are washed with water to eliminate substantiallyall of the salts and acidic agent and to leave them impregnated withsubstantially only sericeous material.

I have observed that substitution of the aqueous solution of an acidicagent by an aqueous alcoholic solution of an acidic agent, in theabove-mentioned procedures, furnishes fibers which contain an increasedproportion of sericeous material. Also, I prefer that the aqueousalcoholic solvent for the acidic agent contain a major proportion byvolume of the alcohol. To illustrate, two samples of the same cottoncloth are impregnated in the same manner and with substantially the sameproportion of the same aqueous solution of alkylolamine-copper complex,sodium hydroxide and sericeous materiahand one impregnated sample iswashed with an aqueous solution of hydrogen chloride and the other withan aqueous alcoholic (say, 85 per cent isopropyl alcohol) solution oftially so in each solution. Afterwards, each sample is washed well withwater and dried. Then it will be found that the cloth washed withaqueous alcoholic acid has gained more proportionally in weight due totreatment than the other cloth, generally will possess a smoother fullerfeel, and usually will be dyed to a deeper or darker color wheneachfabric is dyed in the same manner.

In the above-indicated procedure, treatment of the impregnated fiberswith aqueous alcoholic acid leads to the formation of alkylolaminehydrochloride, copper (cupric) chloride and sodium chloride. Of thesesalts, the alkylolamiue hydrochloride and copper chloride are soluble inthe aqueous alcohol and for the most part will be removed from thefibers during washing with the aqueous alcoholic solution of acid.Sodium chloride,

however, hasa limited solubility in the alcoholic liquid and it isnecessary that the fibers be washed with water sothat this salt as wellas the acid and any residua of copper and alkylolamine salts beeliminated from the fibers. In other words, I seek to prepare fiberswhich are impregnated with substantially only sericeous material and aresubstantially devoid of any salts or acidic agent. I do not mean tolimit my invention to the use ofinorganic or mineral acids as theabove-indicated method can be modified so that organic acids may beemployed. Forexample, cotton cloth impregnated with an aqueous solutionof an alkylolamine-copper complex, sericeous material and potassiumhydroxide can be washed with an aqueous alcoholic (say, per centisopropyl) solution of benzoic acid. Afterwards, the cloth is washedwith some of the aqueous alcohol to eliminate copper benzoate (which issubstantially insoluble in water) as well as unreacted benzoic acid andalkylolamine benzoate. The benzoates of copper and alkylolamine areformed as the result of interaction between benzoic acid and the coppercomplex. Next, the cloth is washed with water to'remove potassium salt.If desired, warm water, e. g., water at a temperature of 50 to 60 C.,may be used in this instance in place of water at room temperature asbenzoic acid is somewhat more soluble in the warm aqueous liquid andemployment of the latter may remove traces of the acid from the treatedfibers.

Still another modification of my invention involves treatment of fibersimpregnated with an aqueous solution of an alkylolamine-copper complex,a tetra-alkylol ammonium hydroxide and sericeous material. In suchcases, the impregnated fibers may be washed, for example, with 90 percent aqueous isopropyl alcohol in which hydrogen chloride is dissolved.Afterwards, the fibers are washed with aqueous alcohol only, since thealkylolamine, tetraalkylol ammonium and copper salts are soluble in theaqueous alcohol. 7

The following examples'will furnish additional illustrations of myinvention but it will be understood that my invention is not to belimited to them.

Example 1.--To an aqueous solution consisting of 3 g. of copper chloride(CuCl2-2H2O) disso1ved in about 20 cc. of water was addedtriethanolamine in smal portions until a dark blue aqueous liquid wasobtained in which all the copper compound was dissolved. The liquid thenwas diluted with water to a volume of 50 cc. In the diluted solution wasdissolved sufiicient solid sodium hydroxide to react with theamine salt(from interaction of triethanolamine with copper chloride) and to givesubstantially 1 per cent of the free or uncombined alkali metalhydroxide. During dissolution of the latter compound, the aqueous liquidwas cooled externally with Water to prevent any appreciable increase inits temperature.

The solution of alkylolamine-eopper complex and alkali metal hydroxidewas admixed with 7 g. of silk fibers the mixture allowed to standovernight at room temperature. Afterwards, water equal to onefifth thevolume of liquid was added to the mixture and the latter thenfiltered toremove any undissolved material.

A sample of bleached cotton cloth was impregnated with this filteredsolution of sericeous material by im mersion in a portion of it forminutes at room temperature. Afterwards, the cloth was allowed to drainat room temperature, washed with aqueous acid (prepared by admixing 1volume of concentrated aqueous hydrochloric acid with 3 volumes ofwater), then washed well with water, and dried. Increase in weight ofthe cloth indicated it contained 1.29 per cent of sericeous material.

Simultaneously, another sample of the same bleached cotton cloth wastreated in like manner with this modification: the acidic solution forwashing the impregnated cloth was prepared by admixing 1 volume ofconcentrated aqueous hydrochloric acid with 3 volumes of substantiallyanhydrous isopropyl alcohol. In this instance, increase in weight of thecellulose material indicated it contained 2.65 per cent of sericeousmaterial.

Example 2.Two grams of copper chloride (CuClz-ZHzO) were dissolved in 20cc. of water and to this solution diethanolamine was added slowly andwith stirring until a clear blue solution of the copper complex wasobtained. Then the aqueous liquid was diluted with water to a volume of50 cc. Next, sufiicient solid potassium iydroxide was dissolved in thesolution to react with the amine salt (formed by interaction ofdiethanolamine with the copper salt) and to furnish substantially 4 percent of the free or uncombined alkali metal hydroxide. This solution ofalkylolamine-copper complex and alkali metal hydroxide was admixed with6 grams of silk fibers and allowed to stand at room temperature for 1hour. During this time the mixture was shaken occasionally. Afterwards,water equal to approximately one-fifth the volume of liquid was added tothe mixture and the latter then filtered to eliminate undissolvedmaterial.

A sample of unbleached cotton cloth was impregnated with some of thisfiltered solution by immersion therein for 30 minutes at roomtemperature. The sample then was allowed to drain at room temperatureand afterwards was washed twice with aqueous acid prepared by admixing 2volumes of glacial acetic acid with 38 volumes of water. Next, thefabric was washed with water and dried. Increase in weight indicated itcontained 1.68 per cent of sericeous material.

Simultaneously, another sample of the same unbleached cotton cloth wastreated in like manner with this modification: the acidic solution forwashing the impregnated textile material was prepared by admixing 2volumes of glacial acetic acid, 2 volumes of water and 36 volumes ofsubstantially anhydrous n-propyl alcohol. in this instance, increase inweight of the sample indicated it contained 4.23 per cent ofimpregnating material.

Example 3.-Copper hydroxide was admixed with water and to the mixturewas added slowly diethanolamine until the copper compound dissolved anda bluecolored solution was obtained. The latter then was diluted withwater to give an aqueous solution in which the concentration of copperWas equivalent to 2.66 g. of copper hydroxide per 100 cc. of liquid. Inthis solution was dissolved sufiic'ient potassium hydroxide to furnishsubstantially 4 per cent of the alkali metal hydroxide. Silk fibers wereadmixed with this solution of copper complex and alkali metal hydroxide(maintained at room temperature) over a period of 1 hour until an excessof the fibers had been added. The liquid then was separated fromundissolved fibers by filtration.

Two samples of unbleached cotton cloth were impregnated separately withsome of the filtered solution. in each instance, the fabric was workedin the liquid at room temperature for 15 minutes, then removed andallowed to drain at room temperature. One of the impregnated fabrics waswashed twice with an acid solution prepared by admixing 5 volumes of percent aqueous lactic acid with 35 volumes of water. Afterwards, thefabric was washed well with water and dried. increase in weight of thissample indicated it contained 0.75 per cent of impregnating material.

The other impregnated fabric was washed with an acidic solution preparedby admixing 5 volumes of 85 per cent aqueous lactic acid, 4 volumes ofwater and 3l volumes of glycerine. In this instance, the acidic solutionwas rather viscous and consequently it was taken up very slowly by theimpregnated cloth. Also, the alkaline bodies and copper complex (presentin the impregnated cloth) reacted slowly with the acid. It was necessaryin this case that the fabric remain immersed in the aqueous alcoholicacid. for approximately 16 hours at room temperature. And during thattime the acidic solution was stirred occasionally to insure, as far aspossible, that the aqueous glycerine solution in contact with the clothwas always acidic in character. Afterwards, the treated cloth was Washedwell with water and dried. Increase in weight of this sample indicatedthat it contained 7.79 per cent of impregnating material.

The two treated samples and also one of the original unbleached cottonmaterial were dyed separately and in each instance the dye bathconsisted of 100 partsof water per 1 part of cloth and 5 per cent (onweight of sample) of a basic dye (Malachite Green). The samples wereimmersed in their respective baths at room temperature, and after 15minutes the temperature of the baths was increased to 65 C. over aperiod of 30 minutes, then kept at 65 to 70 C. for 30 minutes, andafterwards the baths were allowed to cool to room temperature. Then thefabrics were removed, rinsed well with cold water, and dried. Theuntreated cloth was CuClz- 21-120 dissolved in 50 cc. of water was addedtriethanolamine slowly and in small amounts until a deep blue aqueoussolution of the copper complex was obtained. The

liquid then was diluted with water to a volume of 100' cc. In thissolution was dissolved sufiicient sodiumhydroxide to react with thealkylolamine salt (from interaction of alkylolamine and copper salt) andto give substantially 3 per cent of the alkali metal hydroxide. Sill;fibers were admixed with the liquid (keeping the quantity of fibers inexcess of that which dissolved) and the mixture allowed to stand withoccasional stirring for 2 hours at room. temperature.v Afterwards, theliquid was filtered from undissolved fibers.

Two samples of unbleached cotton cloth were impregnated separately atroom temperature withthe filtered solution. One of the impregnatedsamples then was washed with 8 per cent aqueous sulfuric acid in whichwas dissolved 2 per cent of sodium sulfate, afterwards washed withwater, and dried. Increase in weight of this" fabric indicated itcontained 3.36 per cent of sericeous material.

The other sample of impregnated cloth was washed with an 8 per centsolution of benzoic acid in a solvent consisting'of volumes of n-propylalchol and 5 volumes of water. In this instance, three successiveportions of indicated it contained 5.16 per cent of sericeous material.7

As the function of the acid is to react with the copper complex and withthe alkaline agent and thereby precipi tate sericeous material in or onthefibers, the quantity of acid in solution as well as its concentrationshould such that more than sufficient acid fo'r such -reactions ispresent and the liquid in direct contact with the fibers should beappreciably acidic at all times. Because of the small solubility ofbenzoic acid .inwater, it seemed in+ advisable in thisinstancetocornpare the effect of this acid in aqueous solution with that of theacid in aqueous alcohol. If aqueous benzoic a'cidhad been employed, thena large proportion ofalkylolamine-copper complex and alkali metalhydroxide (and consequently of sericeous material) would have beenwashedout of the impregnated fibers prior to reactingfwith the acid dueto thelarge volume of water needed to'dissolve the required quantity ofacid. For these reasons,an acid more soluble in water, namely, sulfuricacid, was used when water only was the solvent. Also, a'small proportionof alkali metal salt was dissolved in the aqueous acid to aid inprecipitation of sericeous material. Employment of an.

aqueous acid containing a small proportion of a dissolved alkali metalsalt in the treatment of textile'fibers iinpregnatedwith analkylolamine-copper' complex and sericeous material has been describedin my copending application Ser. No. 101,499. 7 a

Example 5.-To g. of copper chloride (CuCl2 2H20.)

dissolved in a small quantity of water'was added Z-amino-2-methyl-propanediol-L3' in small portions and with stirring until allof the copper compound was changed into the alkylolamine-copper-complexand a deep blue colored solution was obtained. The latter thenwasdiluted with water to a volume of 100 cc. Next, sufficient potassiumhydroxide was dissolved in the aqueous solution to react with thealkylolamine salt (resulting from interaction of alkylolamine withcopper compound) and to give sub stantially 3 per cent of theu'ncombined alkali metal hydroxide. Silk fibers, in an amount greaterthan that which would dissolve, were admixed with the aqueous solutionand the mixture allowedto'stand for 2 hours at room temperature.Afterwards, undissolved fibers-were separated by filtration.

Two samples of unbleached cotton cloth were impregnated with some of thefiltered solution by immersion therein at room temperature. The twosamples were al' lowed'to drain and to remainexposed to the atmosphereovernight. One of these samples was washed with 10 per cent aqueoushydrochloric aeidfthen with water, and dried. Increase in weight of thissample' indicated it contained 4.43 per cent of sericeous material."

The other fabric was immersed in alO per cent solution of salicylic acidin a solvent consisting of 95 volumes of propylene glycol and 5 volumesof Water; The cloth was permitted to remain immersed'in' this acidicliquid at room tmperature for about 18 hours" (overnight). Afterwards,the sample was removed," washed wellwith cold 1 water, then washed withwarm" water (temperature, 50 to 55 C.), and dried. Increase in weight'ofthis fabric indicated it contained 9.02 per cent sericeous material. I

The reasons for comparing washing of one sample with aqueoushydrochloric acid with washing of the other sample with salicylic acidin an aqueous alcholic solution are similar to those 'given underExample 4 forcomparing the effect of aqueous sulfuric acid with that of'benzo-ic acid in an aqueous alcholic solution.

Example 6.-To a mixture of 2.5 g. of copper hydroxide and 100 cc. of 70per cent aqueous ter.-butyl alchol was added2-amino-2-methyl-propanediol-1,3 in small portions substantiallyanhydrous isopropyl, alcohol. NEXLfthiS until allot the copper compounddissolved and. a deep blue colored solution was obtained. Inthis'solution dissolved sutficientjsolid' sodium hydroxide to give sub-'stantially 2.5 per cent of the alkali metal hydroxide.

This solution was admixed with a relatively large quantity of silkfibers and the mixture allowed to stand at room temperature, withoccasional stirring, until the supernatant liquid possessed only a verylight blue color.

The alcoholic liquid then 'was separated from the treated tained bythem. vThe treatedand washed fibers were.

admixed with 100 cc. of water and the mixture allowed to standovernight. Filtration of the liquid then removed undissolved fibers.This method of preparing aqueous solutions of'sericeous material isdescribed in my copcnding application Ser No.y101,499.

Two bleached cotton cloth samples were impregnated with some of the'filtered aqueous solution of sericeous material, andthen allowedjtodrain and to dry at room temperature. One sample was washed with aqueous10 per cent sulfuric acid, then with water, and dried. Increase inWeight of thissample indicated it contained 552 per cent of'sericeousmaterial.

The other sample was washed with 'per cent aqueous isopropyl alcohol inwhich was dissolved substantially 10 per cent by weight of concentratedsulfuric acid; Afterwards, the sample of cloth was washed with water anddried. Increase in weight of thisfabric indicated it contained 8.48 percent of sericeous material.

Example 7.An aqueous solution of sericeous material was prepared in thefollowing'manner: 14 volumes of water were mixed with 6' volumes ofglycerine and then lithium hydroxidewas dissolved in the aqueousalcoholic liquid in theproportion of 1.2 g. to 20 'cc. of liquid.-

Afterwards, thealkaline solution was saturated with copper hydroxide(Cu(OH)2) lay-admixing the latter with" the alkaline solution'in smallportions and stirring the mixture. When an excess of the copperhydroxide had been added, the mixture of liquid and solid was allowed tostand overnight atroom temperature. Then theresulting blue solutionWas'separated from undissolved copper compound by filtration.

Silk fibers were admixed with the solution of copper compound in theproportion of 5 g. of fibers to 20 cc. of liquid. 'Afterthe mixture hadstood, with occasional stirring, at room temperature for 1- hour, theresulting pound. The diluted mixture was permitted to stand for a few'minutes at room temperature and then was filtered.

Substantially all of the silk fibers had dissolved.

Two samples of the same bleached linen cloth were impregnated with some'of the filtered solution. "After: the samples had drained, one of themwas washed with dilute aqueoushydroch'loricacid, then with water, anddried. Increase in weight of this sample indicated it contained 0.67 percent of impregnating material.

The other impregnated sample, after draining, was washed with threeseparate portions of aqueous alcoholic acid made by admixing 15 volumesof concentrated hydrochloric acid, 15 volumes of Water and 70 volumes offabric was washed well with water, and dried. Increase in its weightindicated it contained 1.53 percent of impregnating materialf j I i 1Example 8.-An aqueous'solution containing substantially 20 per cent oftetraethanol ammonium hydroxide was admixed with copper hydroxide(Cu(OH)2) and the admixture allowed to stand at room temperature, withoc-' casional stirring, until no more of the coppercompound 7 appearedtodissolve. The blue colored solution then was separated fromundissol'ved coppel' hydroxide.

I Silkfibers were admixed with the a ueous solution of copper complexand allowed to stand", with occasional stirring, for 18" hours at roomtemperature. Afterwards, undissol'ved fibers were eliminated byfiltration of the mixture.

Two samples of unbleached cotton cloth were saturated with some of thefiltered aqueous sericeous solution by working therein at roomtemperature. Then both samples were permitted to drain and to dry byexposure to the atmosphere. One sample was washed with dilute aqueoussulfuric acid, then water, and dried. Increase in weight or" thisclothindicated it contained 1.4 per cent or impregnating. material. Thisprocedure, includes the prep aration of aqueous solutions containing,substantially only a tetra-alkylol ammonium hydroxidecopper complex andsilk and the application of such solutions to the treatment of cellulosefibers, is described in my copending applica' tion Serial. No. 221, 323.

The other sample was washed three successive times with portions of anacidic solution prepared by admixing volumes of concentrated sulfuricacid, volumes of water, and 80 volumes of substantially anhydrousisopropyl. alcohol. Next, it was washed with water, and dried. Increasein weight of this fabric indicated it contained 8.03 per cent ofimpregnatingmaterial;

As perviously mentioned in thisspecificat-ion, the alcohols which Iprefer are water-soluble, acyclic, saturated, normally-liquid compounds.I They may be either monohyd roxy or polyhydroxy. The alcohols should besulficiently soluble in water. or should be capable of dissolvingsufficient Water so that the resulting aqueous alcoholic liquid will notcontain less than about 60 per cent by Q volume of the alcohol. Aqueousalcoholic liquids containing a greater proportion by volume of thealcohol, say, 86 or 90 per cent, also are suitable. It necessary ordesirable, the alcoholic liquid may have only a. very small proportionof water, say, 0.5 to 1 per centby volume, and may even be substantiallyanhydrous. Mixtures of alcohols are permissible, provided the totalalcoholic content of the aqueous liquid is not less than about 60 percent.

By the term saturated I- mean that the alcohols do not contain. anyunsaturated (e.g., olefinic or acetylenic) linkages in their molecularstructures. By the term normally liquid Imean that the alcohols areliquids at roomtemperture or thereabouts. Examples of such. alcohols areethyl, isopropyl or ter.-butylalcohol, propylene or trimethylenc glycol,and glycerine. Alcohols which are solids at temperatures appreciablyhigher than room or atmospheric temperature, e.g., mannitol, are notincluded in this invention.

I- have illustrated my procedure with fibers which. have beenimpregnated with aqueous solutions containing, in addition todissolvedsilk fibers, a complexcompound of copper. kylolamine-copper complex, analkali metal hydroxidecopper complex, a tetra-alkylolammoniumhydroxidecopper complex and a tetra-alkyl ammoniumhydroxidecopper complex. The alkylolamines-suitable for my purpose canbe either a primary, secondary or teritary amine or they can be eithermorl'ohydroxy or polyhydroxy compounds. The tetra-alkylol ammoniumhydroxides and the tetra-alkyl ammonium hydroxides may be compounds inwhich all four groups (alkylol' or alkyl) are the same or in which twoor more of these groups differ from the others. My invention isapplicable also to the treatment of cellulose fibers impregnated withaqueous solutions containing, in addition to dissolved silk fibers,other alkali copper complexes, e.g;, thoscformed by'interaction ofammonia or of primary, secondary or tertiary amines with copperhydroxide; Since all these complexes either contain. copper and an.alkaline compound or are the resultof interaction of. a copper compoundwith an: alkaline com pound to furnish a water-soluble substance, Iinclude all Examples of such copper complexes are an" al-' 8 such:complexes under the general term of alkali-copper complex. It shouldb'enoted that the alkaline com ounds may be inorganic (egg ammonia orsodium hydroxide) or organic (e.g;, ethyl'ar'nine or diethanolamine) inchar acter;

The impregnated cellulose fibers may be treated according to thisinvention while they are still wet with the aque'ous solutioncontaining" the copper-complex and dissolved silk" fibers; Or; theii'nprcg'nate'dfibers may be partially or substantially'dry prior totreatment. Preferabl'ythe drying operation is effected at roomoratmosphe'ric temper'ature' or thereabouts' and thereby avoidanyhamiful' action on: the cellulose fibers or on the' s'er'iceousmaterial impregnated therein.

The acidic agents suitable forr'ny purpose can be either inorganic ororganic (carboxylic) com ounds; Illustrations of inorganic acids arehydrochloric, hydrobromic or sulfuric acid. Examples of carboxylic acidsare acetic or benzoic acid. Substituted carboxylic acids such as lacticacid, salicylic acid; chlbracen'c acid and bromobenzo'ic acid may beemployed also. In some instances the hydr'ox'y-subsfit'ut'ed acids, vsuch as lactic or salicylic acid, are particularly applicable since theyfurnish copper salts which exhibit appr'eciable's'olubilities in waterand in alcohol'. Whatever acidic agents are employed, they should meetthe following conditions: 1') should not react in an undesirable mannerwith the aqueous alcoholic liquid, (2') should not be present insufficient concentration in the acqueous alcoholic solution so as toexert any deleterious action of the cellulose fibers or on the sericeousmaterial impregnated therein, and (3) should furnish salts, on reactionwith the alkaline agent and copper complex, which are appreciablysoluble in water or in the aqueous alcoholic liquid or in both.

When cellulose fibers impregnated with an alkali-copper complex andsericeous material are washed with the aqueous alcoholic solutionofacidic agent, the latter should be present in sufficient quantity toreact with all the alkaline agent (if present) and all of the coppercomplex. This step of washing the impregnated fibers requires somewhatmore time than if an aqueous solution of the acidic agent is employed.In the case of polyhydroxy alcohols, such as propylene glycol orglycerine,.which. furnish (when employed in accordance with the methodof this invention) rather viscous solutionsof acidic agent, immersion ofthe impregnated fibers for several hours in the acidic liquid is oftenrequired to elfect substantially complete conversion of the coppersomplex-into the corresponding copper salt. Moreover I do not Wish tobelimited to one washing of the fibers with the aqueous alcoholic solutionof acidic agent. If necessary,-fibers impregnated with alkali coppercomplex and sericeous material may be washed two or more successivetimes and each operation involves employment of an unused portion of theacidic solution.

After the fibres are treated with the acidic solution, they are washedwith the aqueous alcoholic solvent, or with water, or successively withthe aqueous alcoholic solvent and with water. The solvent or solventsused in this operation will depend upon such factors as thealkali-copper complex and the aqueous alcohol and the acidic agentdissolved therein. For example, if cellulose fibers are impregnated withan aqueous solution containing alkylolam-ine-copper complex, alkalimetal hydroxid'e and dissolvedsilk fibers and are washed with an acidicsolution consisting of sulfuric acid dissolved in aqueous isopropylalcohol, then the acid wash should be followed by one with water so asto eliminate any alkali metal sulfate and copper sulfate which may notbe removed by the aqueous alcoholic liquid. Or, if. the same impregnatedfibers be-wa'shed with an acidic solution of benzoic acid in aqueousisopropyl alcohol, then it is essential that the fibers be washed:aitclwards with. aqueous alcohol, to eliminate copper benzoate, prior tothe water wash. In any event, the liquids employedsubsequent totreatment of the fibers with the solution of acidic agent should removesubstantially all salts, acidic agent and alcohol (if not readilyevaporated at room tem perature or thereabout) from the fibers and leavethem impregnated with substantially only sericeous material.

Although I have illustrated the process of this invention by itsapplication to the treatment of cellulose fibers, I do not wish to belimited to the treatment of such fibers. Some of the aqueous solutionscontaining dissolved sericeous material (as a copper-containing complex)and a small proportion of alkaline bodies, as for example thosesolutions described in my copending application Ser. No. 101,499, can beemployed for impregnation of animal fibers (such as wool or silk) withsericeous material. Animal fibers impregnated with such aqueoussolutions or copper-silk complexes and alkaline bodies may be treatedaccording to the method of this invention.

What I claim is:

1. The process for treating textile fibers impregnated with awater-soluble alkali-copper complex selected from the group consistingof alkylamine containing no alkylol groups-, alkylolamin'e-,tetra-alkylol ammonium hydroxide-, and alkali-metal hydroxide-coppercomplexes, and sericeous material which comprises washing said fiberswith aqueous alcohol containing a dissolved acidic agent, and thenwashing the fibers with aqueous alcohol, said aqueous alcohol consistingof an admixture of a saturated acyclic normally-liquid water-solublealcohol and water and containing at least about 60 per cent by volume ofsaid alcohol, and said acidic agent forming salts with said coppercomplex which are soluble in said aqueous alcohol which acidic agentdoes not interfere in any undesirable way with the aqueous alcohol andis present in amount insuflicient to exert any deleterious action on thefibers and sericeous material.

2. The process according to claim 1 in which the water-soluble alcoholis a monohydroxy alcohol.

3. The process according to claim 1 in which the watersoluble alcohol isa dihydroxy alcohol.

4. The process according to claim 1 in which the watersoluble alcohol isa trihydroxy alcohol.

5. The process for treating textile fibers impregnated with awater-soluble alkali-copper complex selected from the group consistingof alkylarnine containing no alkylol groups-, alkylolamine-,tetra-alkylol ammonium hydroxide-, and alkali-metal hydroxide-coppercomplexes, and sericeous material which comprises washing said fiberswith aqueous alcohol containing a dissolved acidic agent, then washingthe fibers with aqueous alcohol, and afterwards washing the fibers withwater, said aqueous alcohol consisting of an admixture of a saturatedacyclic normally-liquid water-soluble alcohol and water and containingat least about 60 per cent by volume of said alcohol, and said acidicagent forming salts with said copper complex which are soluble in asolvent selected from the group consisting of water and said aqueousalcohol which acidic agent does not interfere in any undesirable waywith the aqueous alcohol and is present in amount insufficient to exertany deleterious action on the fibers and sericeous material.

6. The process according to claim 5 in which the acidic agent is amineral acid.

7. The process according to claim 5 in which the acidic agent is amonocarboxylic acid.

8. The process according to claim 5 in which the acidic agent is amonohydroxy monocarboxylic acid.

9. In a process of treating textile fibers impregnated with awater-soluble alkali-copper complex selected from the group consistingof alkylamine containing no alkylol groups-, alkylolamine-,tetra-alkylol ammonium hydroxide-, and alkali metal hydroxide-coppercomplexes, and sericeous material, which comprises washing said fiberswith aqueous alcohol containing a dissolved acidic agent, said aqueousalcohol consisting of an admixture of a saturated acylicnormally-liquid-water-soluble alcohol and water and containing at leastabout by volume of said alcohol, and said acidic agent forming saltswith said copper complex which are soluble in said aqueous alcohol whichacidic agent does not interfere in any undesirable way with the aqueousalcohol and is present in amount insutficient to exert any deleteriousaction on the fibers and sericeous material.

10. The process according to claim 9 in which the water soluble alcoholis a monohydroxy alcohol.

11. The process according to claim 9 in which the water soluble alcoholis a dihydroxy alcohol.

12. The process according to claim 9 in which the water soluble alcoholis a trihydroxy alcohol.

13. The process according to claim 1 which includes the further step ofdyeing the washed textile fibers.

14. The process according to claim 5 which includes the further step ofdyeing the washed textile fibers.

15. The process according to claim 9 which includes the further step ofdyeing the impregnated textile fibers.

16. Textile fibers impregnated with substantially only sericeousmaterial, resulting from the method of claim 1.

17. Dyed textile fibers, the fibers being impregnated with substantiallyonly sericeous material, resulting from the method of claim 1.

References Cited in the file of this patent UNITED STATES PATENTS1,936,753 Dreyfus Nov. 28, 1933 1,955,221 Borner Apr. 17, 1934 2,417,388Whitner Mar. 11, 1947 2,417,389 Whitner Mar. 11, 1947 2,446,682 WhitnerAug. 10, 1948 2,565,832 Whitner Aug. 28, 1951

1. THE PROCESS FOR TREATING TEXTILE FIBERS IMPREGNATED WITH AWATER-SOLUBLE ALKALI-COPPER COMPLEX SELECTED FROM THE GROUP CONSISTINGOF ALKYLAMINE CONTAINING NO ALKYLOL GROUPS-, ALKYLOLAMINE-,TETRA-ALKYLOL AMMONIUM HYDROXIDE-, ALKALI-METAL HYDROXIDE-COPPERCOMPLEXES, AND SERICEOUS MATERIAL WHICH COMPRISES WASHING SAID FIBERSWITH AQUEOUS ALCOHOL CONTAINING A DISSOLVED ACIDIC AGENT, AND THENWASHING THE FIBERS WITH AQUEOUS ALCOHOL, SAID AQUEOUS ALCOHOL CONSISTINGOF AN ADMIXTURE OF A SATURATED ACYCLIC NORMALLY-LIQUID WATER-SOLUBLEALCOHOL AND WATER AND CONTAINING AT LEAST ABOUT 60 PER CENT BY VOLUME OFSAID ALCOHOL, AND SAID ACIDIC AGENT FORMING SALTS WITH SAID COPPERCOMPLEX WHICH ARE SOLUBLE IN SAID AQUEOUS ALCOHOL WHICH ACIDIC AGENTDOES NOT INTERFERE IN ANY UNDESIRABLE WAY WITH THE AQUEOUS ALCOHOL ANDIS PRESENT IN AMOUNT INSUFFICIENT TO EXERT ANY DELETERIOUS ACTION ON THEFIBERS AND SERICEOUS MATERIAL.
 13. THE PROCESS ACCORDING TO CLAIM 1WHICH INCLUDES THE FURTHER STEP OF DYEING THE WASHED TEXTILE FIBERS.